Antivascular Ultrasound Therapy Extends Survival of Mice With Implanted Melanomas

Abstract

The goal of this murine investigation was to evaluate the effect of an antivascular ultrasound treatment on the growth of an implanted melanoma and the consequent survival rate. After the intravenous injection of 0.2 mL ultrasound contrast agent (Definity), therapy ( n = 15) was performed on 1-mL tumors for 3 min with low-intensity continuous ultrasound (3 MHz; 2.4 ± 0.1 W.cm –2 [I SATA]); control mice ( n = 17) received a sham treatment. Mice were euthanized once the tumor had reached 3 mL, and then survival percentage vs. time curves were plotted. The median survival time (time for tumor to reach 3 mL) for the treated group was 23 d and for the control group was 18 d; the difference was statistically significant ( p ≤ 0.0001). Antivascular ultrasound therapy reduced the growth rate of an implanted melanoma and increased survival time. The ultrasound therapy provides a further example of tumor vascular disruption, and its future clinical potential should be investigated. (E-mail: sehgalc@uphs.upenn.edu)